What legal argument could the sellers' lawyer make if sellers were pressured into signing a property sale agreement?

In this scenario, the correct answer is C. The sellers' lawyer could argue that the sellers were under undue influence without independent legal advice. This is a valid legal argument because if the sellers were pressured into signing the property sale agreement without having the opportunity to seek independent legal advice or if they were unduly influenced by someone, the agreement may not be considered valid or enforceable.

Options A, D, and F are not the best choices because they do not directly address the issue of undue influence or lack of independent legal advice. Option B mentions that the contract is enforceable, but it does not address the issue of undue influence or the absence of independent legal advice. Option E specifies coercion, which is related to undue influence, but it does not cover the aspect of lacking independent legal advice.